162 CYTOPLASMIC INCLUSIONS 



granules in haematoxylin preparations than blue granules after the 

 methylene blue method. She concludes that they are separate types of 

 granules, although there is a close relationship. Joyet-Lavergne was not 

 able to decide whether chromidia and volutin are really separate. 



Daniels observed buds on the surface of the karyosome, then bodies 

 in the nuclear sap, and finally in the cytoplasm near the nucleus, but she 

 found no direct evidence as to how they penetrate the nuclear mem- 

 brane. On the basis of these suggestive observations, she concludes that 

 these bodies are derived from the karyosome. With regard to the validity 

 of this conclusion, the comment of Wilson (1928, p. 96) with regard 

 to a similar case in oogenesis is highly pertinent: "To the writer none of 

 these cases yet seems to be satisfactorily demonstrated, and the question 

 is a most difficult one to be settled by studies on fixed material alone." 

 Joyet-Lavergne ( 1926a) calls these protein granules albuminoid reserves, 

 a name far more appropriate than chromidia, which at least implies a 

 nuclear origin. 



Volutin granules are basophilic granules which are also metachromat- 

 ic. Because of their pronounced basophilia, volutin granules have often 

 been linked with chromatin. However, they are negative to Feulgen's 

 stain after hydrolysis, but give a positive reaction when the preliminary 

 hydrolysis is omitted (Reichenow, 1928), a characteristic of free nu- 

 cleic acid. The full Feulgen reaction apparently dissolves this type of 

 volutin granule, so that in Arcella there results a diffuse Feulgen reac- 

 tion in the chromidial net. This is a possible explanation of the positive 

 Feulgen test by the chromidial net of Patell'/na. The volutin granules of 

 Trypanosoma melophagium contain no nucleic acid (van Thiel, 1925), 

 while those of T. equinmii do (Reichenow, 1928). The volutin bodies 

 of r. evansi were not tested in this respect (Krijgsman, 1936), although 

 they are listed as containing nucleic acid. Since reserve bodies are not 

 the same in all species of the genus (some trypanosomes are able to 

 store glycogen while others are not, according to von Brand, 1938), 

 both analyses of the basophilic granules may be correct. 



Volutin granules increase and nuclear granules decrease in trypano- 

 somes which have been treated with atoxyl (Swellengrebel, 1908). This 

 fact in conjunction with the staining reactions of volutin, were inter- 

 preted as indicating a direct nuclear origin — in other words, a type of 

 chromidia. In these experiments the results are probably a degeneration 



